The obligations of landlords and tenants, and the statutory basis for the Private Residential Tenancies Board which deals with disputes, are set out in the Residential Tenancies Act 2004.
The obligations of landlords are set out in section 12 of the Residential Tenancies act 2004:
Obligations of landlords.
12.—(1) In addition to the obligations arising by or under any other enactment, a landlord of a dwelling shall—
(a) allow the tenant of the dwelling to enjoy peaceful and exclusive occupation of the dwelling,
(b) subject to subsection (2), carry out to—
(i) the structure of the dwelling all such repairs as are, from time to time, necessary and ensure that the structure complies with any standards for houses for the time being prescribed under section 18 of the Housing (Miscellaneous Provisions) Act 1992, and
(ii) the interior of the dwelling all such repairs and replacement of fittings as are, from time to time, necessary so that that interior and those fittings are maintained in, at least, the condition in which they were at the commencement of the tenancy and in compliance with any such standards for the time being prescribed,
F29[(ba) provide receptacles suitable for the storage of refuse outside the dwelling, save where the provision of such receptacles is not within the power or control of the landlord in respect of the dwelling concerned,]
(c) subject to subsection (3), effect and maintain a policy of insurance in respect of the structure of the dwelling, that is to say a policy—
(i) that insures the landlord against damage to, and loss and destruction of, the dwelling, and
(ii) that indemnifies, to an amount of at least €250,000, the landlord against any liability on his or her part arising out of the ownership, possession and use of the dwelling,
(d) subject to subsection (4), return or repay promptly any deposit paid by the tenant to the landlord on entering into the agreement for the tenancy or lease,
(e) notify the tenant of the name of the person, if any, (the “authorised agent”) who is authorised by the landlord to act on his or her behalf in relation to the tenancy for the time being,
(f) provide to the tenant particulars of the means by which the tenant may, at all reasonable times, contact him or her or his or her authorised agent,
(g) without prejudice to any other liability attaching in this case, reimburse the tenant in respect of all reasonable and vouched for expenses that may be incurred by the tenant in carrying out repairs to the structure or interior of the dwelling for which the landlord is responsible under paragraph (b) where the following conditions are satisfied—
(i) the landlord has refused or failed to carry out the repairs at the time the tenant requests him or her to do so, and
(ii) the postponement of the repairs to some subsequent date would have been unreasonable having regard to either—
(I) a significant risk the matters calling for repair posed to the health or safety of the tenant or other lawful occupants of the dwelling, or
(II) a significant reduction that those matters caused in the quality of the tenant’s or other such occupants’ living environment,
(h) if the dwelling is one of a number of dwellings comprising an apartment complex—
(i) forward to the management company, if any, of the complex any complaint notified in writing by the tenant to him or her concerning the performance by the company of its functions in relation to the complex,
(ii) forward to the tenant any initial response by the management company to that complaint, and
(iii) forward to the tenant any statement in writing of the kind referred to in section 187(2) made by the management company in relation to that F30[complaint,]
F31[(i) in the case of a tenancy of a dwelling in a rent pressure zone (within the meaning given in section 19(7)), where the tenancy commences on or after the commencement of section 33 of the Planning and Development (Housing) and Residential Tenancies Act 2016, furnish the tenant, in writing, with the following information at the commencement of the tenancy:
(i) the amount of rent that was last set under a tenancy for the dwelling;
(ii) the date the rent was last set under a tenancy for the dwelling;
(iii) a statement as to how the rent set under the tenancy of the dwelling has been calculated having regard to section 19 F32[…].]
(2) Subsection (1)(b) does not apply to any repairs that are necessary due to the failure of the tenant to comply with section 16(f).
(3) The obligation under subsection (1)(c) does not apply at any particular time during the term of the tenancy concerned if, at that time, a policy of insurance of the kind referred to in that provision is not obtainable, or is not obtainable at a reasonable cost, by the landlord in respect of the dwelling.
(4) Subsection (1)(d) applies and has effect subject to the following provisions:
(a) no amount of the deposit concerned shall be required to be returned or repaid if, at the date of the request for return or repayment, there is a default in—
F33[(i) the payment of rent, or any other charges or taxes payable by the tenant in accordance with the lease or tenancy agreement, and the amount of rent or such other charges or taxes in arrears is equal to or greater than the amount of the deposit, or]
(ii) compliance with section 16(f) and the amount of the costs that would be incurred by the landlord, were he or she to take them, in taking such steps as are reasonable for the purposes of restoring the dwelling to the condition mentioned in section 16(f) is equal to or greater than the amount of the deposit,
F33[(b) where, at the date of the request for return or repayment, there is a default in—
(i) the payment of rent, or any other charges or taxes payable by the tenant in accordance with the lease or tenancy agreement, or
(ii) compliance with section 16(f),
and subparagraph (i) or (ii), as the case may be, of paragraph (a) does not apply, then there shall only be required to be returned or repaid under subsection (1)(d) the difference between the amount of rent or such other charges or taxes in arrears or, as appropriate, the amount of the costs that would be incurred in taking steps of the kind referred to in paragraph (a)(ii).]
(5) For the avoidance of doubt, the condition in subsection (1)(g)(i) is satisfied if, after all reasonable attempts, the landlord or his or her authorised agent could not be contacted to make the request concerned.
The tenant’s obligations are set out in section 16 of the act:
Obligations of tenants.
16.—In addition to the obligations arising by or under any other enactment, a tenant of a dwelling shall—
(a) pay to the landlord or his or her authorised agent (or any other person where required to do so by any enactment)—
(i) the rent provided for under the F36[tenancy agreement] on the date it falls due for payment, F37[…]
(ii) where the lease or tenancy agreement provides that any charges or taxes are payable by the tenant, pay those charges or taxes in accordance with the lease or tenancy agreement (unless provision to that effect in the lease or tenancy agreement is unlawful or contravenes any F36[other enactment), and]
F38[(iii) the deposit, if any, provided for under the tenancy agreement,]
(b) ensure that no act or omission by the tenant results in there not being complied with the obligations of the landlord, under any enactment, in relation to the dwelling or the tenancy (and in particular, the landlord’s obligations under regulations under section 18 of the Housing (Miscellaneous Provisions) Act 1992),
(c) allow, at reasonable intervals, the landlord, or any person or persons acting on the landlord’s behalf, access to the dwelling (on a date and time agreed in advance with the tenant) for the purposes of inspecting the dwelling,
(d) notify the landlord or his or her authorised agent of any defect that arises in the dwelling that requires to be repaired so as to enable the landlord comply with his or her obligations, in relation to the dwelling or the tenancy, under any enactment,
(e) allow the landlord, or any person or persons acting on the landlord’s behalf, reasonable access to the dwelling for the purposes of allowing any works (the responsibility for the carrying out of which is that of the landlord) to be carried out,
(f) not do any act that would cause a deterioration in the condition the dwelling was in at the commencement of the tenancy, but there shall be disregarded, in determining whether this obligation has been complied with at a particular time, any deterioration in that condition owing to normal wear and tear, that is to say wear and tear that is normal having regard to—
(i) the time that has elapsed from the commencement of the tenancy,
(ii) the extent of occupation of the dwelling the landlord must have reasonably foreseen would occur since that commencement, and
(iii) any other relevant matters,
(g) if paragraph (f) is not complied with, take such steps as the landlord may reasonably require to be taken for the purpose of restoring the dwelling to the condition mentioned in paragraph (f) or to defray any costs incurred by the landlord in his or her taking such steps as are reasonable for that purpose,
(h) not behave within the dwelling, or in the vicinity of it, in a way that is anti-social or allow other occupiers of, or visitors to, the dwelling to behave within it, or in the vicinity of it, in such a way,
(i) not act or allow other occupiers of, or visitors to, the dwelling to act in a way which would result in the invalidation of a policy of insurance in force in relation to the dwelling,
(j) if any act of the tenant’s, or any act of another occupier of, or visitor to, the dwelling which the tenant has allowed to be done, results in an increase in the premium payable under a policy of insurance in force in relation to the dwelling, pay to the landlord an amount equal to the amount of that increase (“the increased element”) (and that obligation to pay such an amount shall apply in respect of each further premium falling due for payment under the policy that includes the increased element),
(k) F39[subject to section 3A(4) (inserted by section 4 of the Residential Tenancies (Amendment) Act 2015), not assign or sub-let] the tenancy without the written consent of the landlord (which consent the landlord may, in his or her discretion, withhold),
(l) not alter or improve the dwelling without the written consent of the landlord which consent the landlord—
(i) in case the alteration or improvement consists only of repairing, painting and decorating, or any of those things, may not unreasonably withhold,
(ii) in any other case, may, in his or her discretion, withhold,
(m) not use the dwelling or cause it to be used for any purpose other than as a dwelling without the written consent of the landlord (which consent the landlord may, in his or her discretion, withhold), and
(n) notify in writing the landlord of the identity of each person (other than a multiple tenant) who, for the time being, resides ordinarily in the dwelling.
You can refer to the full act here: Residential Tenancies Act 2004.